Conventionally, liquid or cream form agents have been widely used as hair cosmetics such as hair bleaches and hair dyes, but it is difficult to apply these types of hair cosmetics uniformly to the hair. In particular, special skills such as “blocking” or a “two mirror technique” are required to apply the cosmetic to the root of the hair or to the back of the head, and a lot of time is also required to do this.
As a countermeasure for such problems, it has been proposed to simplify the hair dyeing operations by discharging agents in the form of foam. For example, such agents include aerosol type hair dyes in which two agents constituting a two agent type hair dye are discharged in foam form from a discharge vessel of the type in which two aerosol cans are connected (see Japanese Patent Application Laid-Open No. 10-287534) and non-aerosol type agents in which a single agent type hair bleach is discharged from a foamer vessel such as a pump foamer or the like as a foam (see Japanese Patent Application Laid-Open No. 9-227347).
However, in the case of agents using a discharge vessel of the type in which two aerosol cans are connected, the first and second agents are each independently discharged from the aerosol cans; accordingly, irregular mixing of the agents tends to occur, so that there may be instances of irregular bleaching (in other words, discoloration) or non-uniform dyeing. Furthermore, since pressure-resistant vessels and caps made of metal are used in the case of aerosol type discharge vessels, these parts are oxidized and corroded by hydrogen peroxide contained in hair bleaches or hair dyes, and there is a danger that the internal pressure inside such pressure-resistant vessels may rise to an excessive pressure and result in the decomposition of this hydrogen peroxide.
On the other hand, in the case of products in which a foamer vessel is filled with a single agent type hair bleach, this hair bleach is applied to the hair without activating hydrogen peroxide, so that the effect obtained in a single application is insufficient. Accordingly, in order to achieve a sufficiently clear bleaching, this hair bleach must be allowed to stand for a considerable period of time following application (e.g., applied in the morning and rinsed away in the evening or the like), and several applications must be repeated, so that the use of such hair bleaches is complicated. As a result, problems also arise in terms of stickiness of the hair while, for example, the hair bleach is allowed to stand.